Undercutter for sawing logs



y 1931- J. s. VALLEY ET AL 5 I UNDERGUTTER FOR SAWING' LOGS Filed Aug. 27, 1929 gMmtow J3 Va Z Ze 1 7. i? 2% rel Patented May 12, 1931 UNITED 'lATES earner @FFECE e JERRY S. VALLEY AND EARL P. FOR-D, OF MATLOCK, WASHINGTON I UNDERCUTTER FOR SAWING LOGS Application filed August 27, 1929 Serial No. 388,788.

This invention relates to what are known as undercutters used for the purpose of holding a saw to its work and particularly designed to be used for cutting a tree up into logs when the tree has fallen to the ground and cannot be cut from the top in the ordinary way because of strain on the saw which would act to pinch the saw.

The general object of this invention is to provide an undercutter of this character which is readily adjustable and which will exert a spring tension on the saw, which spring tension may be adjusted to suit any particular need.

A further object is to provide a device of this character in which this adjustment may be readily and simply made.

Other objects will appear in the course of the following description;

Our invention is illustrated in the accompanying drawings, wherein Figure 1 is a side elevation of an undercutter constructed in accordance with our invention;

Figure 2 is a section on the line 2-2 of Figure 1; 1

Figure 3 is a side elevation of the spring engaging disk looking toward the toothed face thereof;

Figure 4 is a top plan view of the spike.

Referring to these drawings, it will be seen that our undercutter comprises the spike designated generally 10 which may be made of carbon steel of any suitable length and is chisel pointed at 11. This spike at its upper end is formed to provide a driving head 12 and has an aperture 13 for the passage of the bolt 14. The bolt 14: has a screwthreaded portion extending through the aperture 13 and provided with a wing nut 15. This bolt beyond the screw-threaded portion is longitudinally slotted at 16 to receive the recurved end 17 of a flat, stifi leaf spring 18. This end 17 at one side is cut away at 17a to lock the leaf spring and bolt against relative slidin movement.

Mounted upon the bolt is a disk 19, that face of the disk which confronts the spike head 12 being formed with teeth 21 and a recess 22, the head 12 having a lug or tooth 20 engageable between the teeth or in the recess 22. These teeth 21 are radial to the cen- 'ter and extend half around-the disk, the

returned end of the spring 18 extending diametrically of the disk half way between the end of this series of recesses. Diametrically opposite the middle of this series of teeth 21, the inner face of the disk is notchedor recessed at 22. That faceof the disk 19 which confronts the edge of the spring 18 is notched to receive this spring as at 23 so that the disk is thus held rigidly with the spring and with thefbolt. j I

Mounted upon the opposite end of the spring 18 from the disk 19 is a bearing wheel or saw-engaging roller 24: preferably formed with a'plurality of peripheral grooves in any one of which the back of the saw may engage. This wheel is rotatably mounted uponabolt or pin 25 which is bifurcated to embrace the end of the spring 18 and is pinned thereto by pins 26. e j v In the use of this undercutter, thespike 10 is driven into a log and the spring supported roller 24 bears against the back of the saw, the resilience of the spring 18 acting to hold 1 the saw to its Work. It will be seen that the spike may be driven into any part of the log and at any desired inclination and that the spring may be rotatably adjusted with relation to the spike at any desired angle and that when the spring and spike have been ad- I j usted in proper relation, such adjustment may be held by turning home the nut 15.

It will be understood that in the use of devices of-this character, when a tree falls it sometimes happens onunlevel ground that the tree rests on the top and the butt only, In such cases, it cannot be sawed from the top e without the saw being pinched and must be sawed from underneath. Under these cir-' cumstances a wedge-shaped piece is out outof the upper portion of thetrunk ofthe tree, The saw is worked upward from beneath to do the balance of the cutting. The staff or spike 10 .is'driveninto the log, the spring holding the pulley or roller adjusted, and the saw set on top of the roller in one of the grooves and the operator proceeds to cut upward. As the cutting proceeds, the wedgeshaped piece previously cut out will prevent the log from splitting until the cuts come near enough together that what is left uncut will break squarely ofi. The teeth 21 on the disk 19 do not need to extend all around the circle as the spring could not be used to set over against the log which a continuousseries of teeth would permit of. The one notch 22 is adapted to engage with the tooth 20 on the spike when the spike is disposed in parallel relationto thespring' sothat the device may be folded up for packing or carrying.

Attention is particularly called to the style of the notches in the disk 19.. These are designed to produce a positive lock and to hold the "saw" permanently to its position, relying on the elasticity of the spring for the force with which the saw is fed into the wood; Heretoforein devices known to us, this part has been extremely-complicated and is relatively'hardto adjust and there has been liability of slippage; Our positive lock does awaywith both. ofthese troubles and at the same time we pnovide a device which is lighter in weight for the operator to carry in the woods. The roller 24- Will'preferably be self.- oilingn and, therefore, preferably hollow. This forms no part of our present invention.

We claim 1. A saw supporting device for*und-ercutting including a spike adapted to be driven into a log, a bolt extending throughthe spike, stifit' leaf springv having one end returned upon itself, the bolt 'having'a slot through which'thereturned end of the'lea f spring passes, the free end of the spring carrying a roller adapted to engage the saw, and means carried by; the bolt whereby the spike and spring may be rigidly engaged to each other 0 in aplurality of difierent angularrelations.

2. A saw supporting device for undercutting comprising a spike adapted to be driven intoalog, a bolt extending through the spike and screw-threaded at one end, the other end 7 w of thebolt being slotted, a disc mounted upon the bolt, the confronting faces of the-disc and spike being formed one with a tooth and the other with coacting notches, the opposite face of the disc having diametrically disposed notches, a stiffleaf spring having one end returned upon itself and disposed in said slot and engaged with the last nained notches on: the disc, the'freeend of the spring carrying a laterally, projecting pin, and a'roller adapted to engage-against the back; of a saw, and aunt engaging the bolt and bearing against the spike.

In testimony whereof we hereunto affix our signatures; 69? JERRY-S. VALLEY.

EARL P; FORD. 

